JDBC GS execute method summary

Statement's execute()
methods for SQL DML and SQL DDL queries?

This method (execute()) can executes any SQL statement, which
may return multiple results.

Normally you can ignore this multiple results futures unless you are
executing a stored procedure that you know may return multiple results.

The Statement interface has these methods for that:

Methods in Statement interface

Description

boolean execute(String sql)

Executes the given SQL statement, and returns
true if the first result is a ResultSet object; false if it is an update
count or there are no results.

boolean execute(String sql, int autoGeneratedKeys)

Same as
execute(String sql)
but for a SQL INSERT you
can signals the driver a given flag about whether
the auto-generated keys produced by this Statement object
should be made available for retrieval.

boolean execute(String sql, int[] columnIndexes)

Same as
execute(String sql)
but for a SQL INSERT you
can signals the driver that
the auto-generated keys indicated in the given array should be
made available for retrieval.
The array contains the indexes (starting with 1 for the first) of the columns.

boolean execute(String sql, String[] columnNames)

Same as
execute(String sql)
but for a SQL INSERT you
can signals the driver that
the auto-generated keys indicated in the given array should be
made available for retrieval.
The array contains the names of the columns.

As SQL statements used with an execute() method can lead to a ResultSet result, then you
may be need to read the ResultSet data.

The three last methods above can result in a possibility to retrieve the
auto generated key for a INSERT SQL.

The Statement interface has some methods that
help you to retrieve such things after an SQL execute() method:

Methods in Statement interface

Description

ResultSet getResultSet()

Retrieves the current result as a ResultSet object. This method
should be called only once per result.

int getUpdateCount()

Retrieves the current result as an update count; if the result is a
ResultSet object or there are no more results, -1 is returned.
This method should be called only once per result.

boolean getMoreResults()

Moves to this Statement object's next result,
returns true if it is a ResultSet object, and implicitly
closes any current ResultSet object(s) obtained with the method getResultSet.

ResultSet getGeneratedKeys()

Retrieves any auto-generated keys created as a result of
executing this Statement object. If this Statement object did not
generate any keys, an empty ResultSet object is returned.

To test for multiple ResultSet you can use this:

// There are no more results when the following is true:// stmt is a Statement object
((stmt.getMoreResults() == false) && (stmt.getUpdateCount() == -1))